Forging or stamping swage



Dm 22, 1942. F. BAYER 2,305,803

FORGING OR STAMPING SWAGE Filed July 6, 1939 Patented Dec. 22, 1942 FORGING R STAMPING SWAGE Franz Bayer, Berlin-Reinickendorf, Germany; vested in the Alien Property Custodian Application July 6, 1939, Serial No. 283,012 In Germany August 7, 1937 Claims.

This invention relates to forging or stamping swages, the cavities of which are in communication during forging with the outer air through vents.

It is known that in forging metal articles in swages with cavities of large dimensions, compression of the air, or gas, occurs in the interior of the latter, and has an unfavourable influence on the shape of the article and on the working life of the swage.

As a remedy, it has already been proposed to connect the interior of the swage with the outside air by providing bores through which the air can escape. The provision of bores, however, has disadvantages. For example, there is no certainty of the air being completely expelled from the space between the workpiece and the bottom of the swage, inasmuch as, owing to the often irregular flow of the material, the bores become choked, with the result that air pockets can, nevertheless, remain in the interior of the swage. Another drawback of swages provided with bores consists in that the bores lead to the formation of undesired nipples on the workpiece, in the interior of the swage. In general, no projecting portions other than those conforming with the shape of the workpiece should be present when the material of the latter is one in which--for example, in the case of alloys of magnesium or aluminiumthe arrangement of the fibres plays an important part. For this reason such forgings are mostly produced in swages unprovided with air vents.

The present invention aims at enabling swages to be effectively evacuated, and at preventing the formation of undesired projecting portions on the workpiece. With that object, in the case of forging or stamping swages, the upper and/or lower members of which contain die cavities bounded by parts fitting one into the other, the joints situated between said parts of the swage members and not,

in themselves assuring the evacuation of the swage, are widened in accordance with the invention to form air gaps opening into the said cavities and communicating with the venting bores leading to the outside. The air gaps may be so narrow that the material of the forging cannot possibly penetrate them. One or the other of the interpenetrating parts may be provided, at the end of the narrow air gap, with,a groove which, in turn, communicates with the bores leadin to the outside. In this manner, notwithstanding the narrowness of the gap, a sufliciently large evacuation aperture is obtained, accompanied by a long working life of the swage parts.

In order that the invention may be more clearly ing drawing, which illustrates diagrammatically and by way of example, one embodiment thereof.

In said drawing, the upper member of the swage consists of the parts I, 2 and the lower member of the parts 3, t. a manner as to form, in the joints extending along the lines of the largest cavities of the swage, air gaps 5 which communicate with the outer air by way of one or more bores 6 in the parts I, 3. Said air gaps 5 may be so narrow (for example, about 0.15 mm. in diameter) that none of the material under treatment can enter them. The air gaps 5 preferably terminate in annular grooves I which,

in the example shown, are machined in the parts- 2, 4; though they may also be provided in the parts I 3, or in all parts appertaining to the swage.

I claim:

1. A forging or stamping swage comprising a part having a recess therein, a second part seated in said recess and cooperating with said first part to form a die cavity, an air gap opening into said cavity and extending continuously around said second part along the plane of separation of said parts, said gap being of such small dimensions that material of the forging cannot enter, and a venting bore leading from said air gap through the said first part to the outside.

2. A forging or stamping swage as claimed in claim 1, wherein a plurality of venting bores are provided and are connected by a groove formed in one of said parts to enlarge said air gap along the margin thereof .which is remote from the die cavity.

3. A forging or stamping swage comprising a part having a recess therein, a second part seated in said recess and cooperating with said first part to form a die cavity, said second part including a portion in contact with the interior walls of said recess and a portion which is spaced away from said walls outside the said die cavity to form an air gap communicating with said die cavity, the

spacing of said parts being so small that the material of the forging or stamping cannot enter said FRANZ BAYER. v

The division is carried out in such 

